To control AOP systems (AOP=Advanced Oxidation Process) for oxidative treatment, i.e. the oxidative preparation, purification and/or disinfection of water, parameters are currently used which give information about the composition of the water matrix and therefore determine scavenging of the generated radicals only indirectly. At present only the “conventional” parameters such as TOC, turbidity, UV-T and the measurement of specific parameters such as dissolved ozone or hydrogen peroxide are used to control AOP systems. These parameters are time-consuming to measure and the equipment to do so is usually expensive. Linking these parameters for control purposes is complex and depends on many different factors. Furthermore, the correlation between dose and effect (e.g. degradation of trace substances) is not known or can only be measured in a manner that is time-consuming since substance-specific analyses have to be carried out.
The scavenging (consumption) of OH radicals by the water matrix and measurement of this scavenging is so far unknown. At present too many OH radicals are produced in some installations (and consequently there is higher consumption of operating materials) in order to prevent the effect of “radical scavenging” (“scavenging”). Radical scavenging is caused by organic and inorganic substances that may be naturally present in water, such as carbonates for example.
CN 1869684 A, which is incorporated by reference herein, relates to a device and a method for measuring the oxygen demand of aerobic microorganisms during waste water treatment.
US 2006 240558 A, which is incorporated by reference herein, proposes a device and a method for determining the chemical oxygen demand (COD) of a water sample.
CN 1372141 A, which is incorporated by reference herein, discloses a test and evaluation method for the organic biobody degradation in water to attain extensive water quality targets using inter alia the parameters BOD5/COD, CO2 formation and ATP.
JP 9292388 A, which is incorporated by reference herein, relates to a method for determining the degradation of a thin film of lubricant based on a fluorine-containing resin, with the concentration of fluoride ions being measured.
EP 0 388 590 A2, which is incorporated by reference herein relates to a method for determining organic compounds including all degradation products in a gas or liquid phase, with the gaseous or liquid sample material being transferred into a limited quantity of water in which the organic compounds are photolytically decomposed. The decomposition products are detected in a carrier gas and/or in the limited quantity of water.
DE 43 16 452 C1, which is incorporated by reference herein, describes a method for the degradation of polymeric organic pollutants in water by means of the AOP combination UV and hydrogen peroxide; there is no mention of a measuring method, however.
US 2010/0206787 A1, which is incorporated by reference herein, proposes a system for the treatment of liquids by means of UV radiation and an oxidising agent in an advanced oxidation process (AOP). The system is controlled by a regulating process, with the described measuring technique using two chemical sensors and determines the oxidizing agent content, in particular ozone, in the liquid phase and then controls the UV dose.
US 2008/0179178 A1, which is incorporated by reference herein, discloses a UV reactor for purifying waste water, likewise based on the AOP method. A UV light source and a titanium dioxide layer are used as catalyst to produce hydroxyl radicals, wherein this relates to the construction of the UV reactor required for this purpose for large-scale use and not to a measuring method for OH-radicals.
EP 1 008 556 A2, which is incorporated by reference herein, presents a method for the decontamination of polluted waste water by means of light radiation and ultrasound, i.e. a combined photo- and sonochemical treatment, it being possible for oxidizing agent such as ozone to also be used; there are no references to a measuring method, however.
A method for determining the radical scavenging potential of a water and its use for the efficient control of the consumption of operating materials in an AOP system has not been known until now.
It is therefore the object of the present invention to optimise or reduce the consumption of operating materials in ATP systems and methods and facilities for the oxidative treatment of water. In particular it is an aim of the present invention to disclose a method and a device for controlling a process for the oxidative treatment of water.